"Which" have published a report of tests conducted on:

Shell V-Power (petrol)

BP Ultimate Diesel and

Tesco Super Unleaded

In short, they concluded these fuels and similar offer no benefit to the driver in terms of performance or economy and in one test economy and emissions got worse. They also concluded the only place the motorist would be affected would be in the pocket.

I beg to differ, Shell Optimax (as it was called) made a marked difference to my Saxo VTR and I've always used Shell V-Power Diesel in the vRS. I guess it comes down to personal preference, what you actually notice on the car (subjective of course) and whether you really want that Ducati Speed Trolley bag after collecting the points...

In short, they concluded these fuels and similar offer no benefit to the driver in terms of performance or economy and in one test economy and emissions got worse. They also concluded the only place the motorist would be affected would be in the pocket.

This is my experience with BP ultimate and Shell Optimax diesel too. :thumbdwn:

I beg to differ, Shell Optimax (as it was called) made a marked difference to my Saxo VTR and I've always used Shell V-Power Diesel in the vRS..

Pah, what would scientists know eh, leave it to someone in a saxo with a right foot to judge it :P

Cheap diesel and millers DPS 4 FTW

Shell extra and Millers DPS 4 everytime it needs juice.

Car feels crap on anything else, and as Shell are normally price matching the cheapest in the area, it best value for money where i am concerned.

Its only common sense that if a petrol engine is designed to run on low octane fuel then using very high octane fuel will not make much differance. My wife's Polo 1.4 16V 75PS certainly, I would expect, show no improvement to MPG or power, but my Passat V6 should show an improvement to MPG and power as it is meant to be used with this fuel - but will happily run on lower octane fuel. I'd expect diesel engines designed to run on the higher cetane fuels would show an improvement. As far as I know, the VRS etc PDI is just a "cooking" biggish engine in a smallish car - as opposed to a "balls out" sports diesel engine.

I've always trusted Which to try to stop some people enjoying them selves - they try to force standardisation on a world that likes to make personal choices.Their consumer guides should just be taken as that - ie a list of thing that might or might not interest you, and that you might or might not have thought about!

This is my experience with BP ultimate and Shell Optimax diesel too. :thumbdwn:

Me three!

Even the Octy doesnt run any different or give me extra MPG - infact, exactly the opposite. MPG is worse on these performance fuels.

mine seems to run crap on standard unleaded and on tescos 99 too.

I would say they are only really of benefit if your car was mapped for it, on my old mk2 Octy vRS it would run like a dog on 95RON, but flew on V-Power / Optimax.

I am also guessing that they just picked a pretty much bog standard motor to do the testing in?

I'm still not convinced on Performance diesel's yet though, I use regular shell and millers in the vRoomster and it runs fine on that.

mine seems to run crap on standard unleaded and on tescos 99 too.

IME no 2 cars run the same on any fuel. My Octy hates anything but BP and Tesco 95 ron petrol. It's more 'pert' as SWMBO says on 99ron, but at higher cost and 5-7MPG LESS.

Works Mondy runs crap on anything but Texaco derv, but I use BP for the nector points

My mk1 1.8T loved Total 95ron, and ran very lumpy, and turbo lagged on everything else.

Now i'm not clued up on Diesels, but i know for a fact that with V power i've seen the difference on the Dyno and all the extra timing you can put in for extra BHP.

If i put anything else in my car it WILL DET as she's mapped for V power.

But i also now if you put a higher octane fuel in a car not set up for it, there will be no gains and i can believe the claims of worse MPG.

BBC NEWS | Business | Row over quality of super fuels

Unless your chasing power gains i certainly would use a 'Super fuel'

I run my Fabia vRS on regular diesel.

Tried a tank of V-Power, and it felt slightly smoother, but the economy was noticeably worse (~20 miles less than I usually get)

depends on your engine... did you all note the report said "VW's twincharged engine reponded really well to shell v-power......" it may have been the exception, but the more highly tuned the more benifit....

fifth gear did a similar test, and when in a 1.6 petrol focus, standard unleaded, and v-power had absolutley no difference, but in a tune imprezza, the v-power gave almost an 15 bhp increase!

my experiance..... BP ultimate (diesel) , better fuel economy, no power differnce, (even feels a bit flatter) , but I had a RR done with standard diesel, and then a RR done (no other mods AT ALL, same RR (awsome) , and got a 7.5bhp increse for using v-power diesel.... they are my findings... the graphs can be seen at awsomes website... funny though, this 7 bhp was at the wheels, same figure at the flywheel.......

Cheap diesel and millers DPS 4 FTW

Aye shell extra is the same price as normal derv, but the V-power gives poorer economy and not much more.

The BP ultimate is good for a clean out, but economy isn't really effected either way. I noticed a lot more soot for a small bit, then a lot less soot for a while after the tank.

Thing is DPS4 does it all for a fraction of the price.

Aye shell extra is the same price as normal derv, but the V-power gives poorer economy and not much more.

The BP ultimate is good for a clean out, but economy isn't really effected either way. I noticed a lot more soot for a small bit, then a lot less soot for a while after the tank.

Thing is DPS4 does it all for a fraction of the price.

I agree completely with you on this, people should understand that there is more to "fuel" than just giving you more or same power, the quality branded fuels claim, and they would be hammered for this by the "authorities" (magazines) if proven wrong, that they clean up or help keep clean the engine induction and combustion areas - doing that job is what can, longterm keep/make the engine "run better" - also there is in somes the possibility of more power and/or better economy.

What everyone so far has missed completely is that Shell is the fuel of champions - ie Ferrari - and they have not had any FIA rulings go against them (the ba---rds!) - so it does work wither its right or honest or anything else (hope it doesn't work so well this weekend tho!).

BBC NEWS | Business | Row over quality of super fuels

The report said that Shell V-Power gave a 1.6-litre Ford Focus a marginal power increase, but filling the car on this petrol for 12,000 miles would cost £115 more than using Shell's standard petrol.

The magazine's findings suggested that Tesco's Super Unleaded decreased the power of the Ford Focus.

Which? also tested a diesel super fuel and said that BP Ultimate diesel made the fuel economy and performance of a Renault Megane 1.5 slightly worse.

My thought was if the Focus 1.6 is made to run on 97+RON fuels in the same way that the Skodas are?

A single car sample is pretty poor evidence also.

I used to read the which magazine but I stopped when I got the feeling that their research was often flawed, this seems to be a classic example.

Thorney Motorsport Fuel Test Results

This is a more definative test of different fuels.

A 1.6 litre Focus will be designed to run on 95 RON, putting V-power in it (98 RON) won't gain you anything at all and will use more fuel as the ECU will have to try and compensate for the unsuitable fuel.

A high compression engine, like in my Swift Sport, needs V-power to run best to prevent pre-ignition. It will run on 95 but you can feel it loses a bit of power and economy is worse.

You can't say the likes of V-power is not worth it, if you are using it in a car that doesn't require it.

OK so is it worth putting in super diesel into a 2.0 pd 140? I do a lot of miles and it costs a fortune at the moment, I could save 10% if it was not worth it

I don't think anyone at Which has any science or statistics training.

A sample size of 1 is nothing to base a conclusion on.

Even my ST will run on 95ron just fine so I'm sure the 1.6 will..

Ahh so you buy v-power derv and then it go's to the FIA via Ferrari as backhanders... got you